Method for Making a Bit of a Tool

ABSTRACT

Disclosed is a method for making a bit of a tool. The method includes the steps of providing a blank, forging, cutting and pressing. The size of the blank is determined according to the size of the bit. By the forging, the blank is made with a connective section and a neck. The connective section is formed with a polygonal profile, a first chamfer at an end thereof and a second chamfer at another end thereof. The neck extends from the polygonal connective section and includes ribs separated from one another by grooves. By the cutting, the neck is made with a tapered section. By the pressing, the tapered section of the neck is turned into a driving section of the bit to reduce the length of the tapered section of the neck but increase the width of the tapered section of the blank.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a tool and, more particularly, to an efficient, effective and inexpensive method for making a bit of a tool.

2. Related Prior Art

Referring FIGS. 1 and 2, there is shown a conventional method for making a bit of a tool. At first, a circular rod is provided. Secondly, the circular rod is turned into a hexagonal rod by drawing. The width of the hexagonal rod is smaller than the diameter of the circular rod. Thirdly, a section with a predetermined length is cut from the hexagonal rod. The section cut from the hexagonal rod will be referred to as the “blank” for clarity in the following description. Fourthly, a chamfer 13 and notches 12 are made on the blank by cutting. Fifthly, a circular section 14 and a tapered section are made on the blank by cutting. The hexagonal section of the blank made with the chamfer 13 and the notches 12 is referred to as the “connective section 11.” Sixthly, four cutouts are made in the circular and tapered sections of the blank by cutting, thus forming a cruciform section of the bit. The cruciform section of the bit is referred to as the “driving section 15.” In use, the connective section 11 of the bit is inserted in a corresponding cavity defined in a shaft of a manual or electric tool.

There are however several problems with the conventional method for making the bit. At first, it requires and wastes a lot of material to make the bit because the connective section 11 of the bit is solid and because the driving section 15 of the bit are formed by cutting an excessive amount of material from the blank. Secondly, there is room for improvement regarding the yield. The conventional method includes quite a few steps and the chance of an error occurring at any of the steps is high. Thus, the yield is affected. Thirdly, there is room for improvement regarding the efficiency. It takes a long period of time to execute the conventional method since it includes many steps.

The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.

SUMMARY OF INVENTION

It is the primary objective of the present invention to provide an efficient, effective and inexpensive method for making a bit of a tool.

To achieve the foregoing objectives, the method includes the steps of providing a blank, forging, cutting and pressing. The size of the blank is determined according to the size of the bit. By the forging, the blank is made with a connective section and a neck. The connective section is formed with a polygonal profile, a first chamfer at an end thereof and a second chamfer at another end thereof. The neck extends from the polygonal connective section and includes ribs separated from one another by grooves. By the cutting, the neck is made with a tapered section. By the pressing, the tapered section of the neck is turned into a driving section of the bit to reduce the length of the tapered section of the neck but increase the width of the tapered section of the blank.

Other objectives, advantages and features of the present invention will be apparent from the following description referring to the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be described via detailed illustration of several embodiments versus the prior art referring to the drawings wherein:

FIG. 1 is a flow chart of a conventional method for making a bit of a tool;

FIG. 2 is a perspective view of the bit made by the conventional method shown in FIG. 1;

FIG. 3 is a flow chart of a method for making a bit of a tool according to the first embodiment of the present invention;

FIG. 4 is a perspective view of the bit made by the method of FIG. 3;

FIG. 5 is a flow chart of a method for making a bit of a tool according to the second embodiment of the present invention;

FIG. 6 is a perspective view of the bit made by the method of FIG. 5;

FIG. 7 is a flow chart of a method for making a bit of a tool according to the third embodiment of the present invention;

FIG. 8 is a perspective view of the bit made by the method of FIG. 7;

FIG. 9 is a flow chart of a method for making a bit of a tool according to the fourth embodiment of the present invention; and

FIG. 10 is a perspective view of the bit made by the method of FIG. 9.

DETAILED DESCRIPTION OF EMBODIMENTS

Referring to FIG. 3, there is shown a method for making a bit 20 of a tool as shown in FIG. 4 according to a first embodiment of the present invention. The bit 20 includes a neck 25 extending between a connective section 21 and a driving section 28.

At first, there is provided a blank in the form of a circular rod. The length and diameter of the blank are determined according to the size of the bit 20 so that the volume of the blank is substantially identical to the volume of the bit 20.

Secondly, the blank is made with a first section and a second section by forging. At least one mold is used during the forging. The first section of the blank includes a hexagonal profile thereon, a cavity 22 defined therein, a first chamfer 23 formed at an end of the hexagonal profile and a second chamfer 24 formed at another end of the hexagonal profile. The first section of the blank is referred to as the “connective section 21” of the bit 20. The second section of the blank includes four ribs 26 separated from one another by four grooves 27.

Thirdly, a tapered cruciform section is formed on the blank by cutting the second section of the blank. The second section of the blank except the tapered cruciform section is referred to as the “neck 25” of the bit 20.

Fourthly, the blank is punched or pressed axially. Thus, the length of the blank is reduced while the width of the tapered cruciform section of the blank is increased. Now, the bit 20 is completed. The enlarged tapered cruciform section of the bit 20 is referred to as the “driving section 28.”

In use, the connective section 21 of the bit 20 is inserted in a compliant cavity defined in a shaft of a manual or electric tool. A spring-biased detent provided on the shaft is located against the second chamfer 24 to retain the connective section 21 of the bit 20 in the cavity of the shaft. The driving section 28 of the bit 20 is inserted in a compliant cavity defined in a screw. The screw is driven by the bit 20 as the manual tool is operated or the electric tool is turned on.

Referring to FIGS. 5 and 6, there is shown a method for making a bit 30 of a tool according to a second embodiment of the present invention. The bit 30 includes a neck 35 extending between a connective section 31 and a driving section 38.

At first, there is provided a blank in the form of a hexagonal rod. The length and width of the blank are determined according to the size of the bit 30 so that the volume of the blank is substantially identical to the volume of the bit 30.

Secondly, the blank is made into the bit 30 by forging. At least one mold is used during the forging. As mentioned above, the bit 30 is formed with the connective section 31, the neck 35 and the driving section 38. The connective section 31 of the bit 30 is made with a cavity 32 defined therein, a first chamfer 33 formed at an end thereof and a second chamfer 34 formed at another end thereof.

Referring to FIGS. 7 and 8, there is shown a method for making a bit 40 of a tool according to a third embodiment of the present invention. The bit 40 includes a neck 45 extending between a connective section 41 and a driving section 48.

At first, there is provided a blank in the form of a circular rod. The length and diameter of the blank are determined according to the size of the bit 40 so that the volume of the blank is substantially identical to the volume of the bit 40.

Secondly, the blank is made into the bit 40 by forging. At least one mold is used during the forging. As mentioned above, the bit 40 is formed with the connective section 41, the neck 45 and the driving section 48. The connective section 41 of the bit 40 is made with a hexagonal profile, a cavity 42 defined therein, a first chamfer 43 at an end of the hexagonal profile, and a second chamfer 44 at another end of the hexagonal profile. The width of the neck 45 is smaller than the diameter of the blank. The neck 45 is made with six ribs so that it looks like a flower in a cross-sectional view. The driving section 48 of the bit 40 is formed with six ribs so that it looks like a flower in a cross-sectional view.

Referring to FIGS. 9 and 10, there is shown a method for making a bit 50 of a tool according to a fourth embodiment of the present invention. The bit 50 includes a neck 55 extending between a connective section 51 and a driving section 58.

At first, there is provided a blank in the form of a circular rod. The length and diameter of the blank are determined according to the size of the bit 50 so that the volume of the blank is substantially identical to the volume of the bit 50.

Secondly, by forging, the blank is made with the connective section 51 and the neck 55. At least one mold is used during the forging. The connective section 51 of the bit 50 is made with a hexagonal profile, a cavity 52 defined therein, a first chamfer 53 at an end of the hexagonal profile, and a second chamfer 54 at another end of the hexagonal profile. The neck 55 is made with a circular profile. The diameter of the neck 55 is smaller the diameter of the blank.

Thirdly, by squeezing, a portion of the neck 55 is made into the driving section 58. At least one mold is used during the squeezing. The driving section 58 of the bit 50 is flat. The driving section 58 of the bit is inserted in a groove defined in a shaft of a manual or electric tool.

The bit of the present invention uses a small amount of material for several reasons. At first, the connective section 21, 31, 41, or 51 of the bit 20 30, 40 or 50 is hollow instead of the solid connective section of the bit made in the method addressed in the Related Prior Art. Secondly, the connective section 21, 31, 41, or 51 of the bit 20 30, 40 or 50 is shorter than the solid connective section of the bit made in the method addressed in the Related Prior Art.

Only a small amount of material is wasted or no material is wasted at all. The grooves 27 are made by forging instead of cutting.

Moreover, the method of the present invention is effective and efficient. The method of the present invention includes only a few steps. Hence, the chance of an error occurring at any of the steps is low. That is, the yield of the method is high. Conclusively, the bit made by the method of the present invention is light in weight and inexpensive in cost.

The present invention has been described via the detailed illustration of the embodiments. Those skilled in the art can derive variations from the embodiments without departing from the scope of the present invention. Therefore, the embodiments shall not limit the scope of the present invention defined in the claims. 

1. A method for making a bit of a tool including the steps of: providing a blank with a size according to the size of the bit; forging the blank so that it includes: a connective section formed with a polygonal profile, a first chamfer at an end thereof and a second chamfer at another end thereof; and a neck extending from the polygonal connective section and including ribs separated from one another by grooves; cutting the neck to provide a tapered section; turning the tapered section of the neck into a driving section of the bit by pressing to reduce the length of the tapered section of the neck but increase the width of the tapered section of the blank.
 2. The method according to claim 1, wherein the connective section of the bit includes a cavity defined therein.
 3. The method according to claim 1, wherein the driving section of the bit is cruciform.
 4. A method for making a bit of a tool including the steps of: providing a blank with a size according to the size of the bit; providing at least one mold; forging the blank into the bit with the mold so that the bit includes: a connective section with a hexagonal profile, a cavity defined therein, a first chamfer at an end thereof, and a second chamfer at another end thereof; a neck extending from the connective section, wherein the width of the neck is smaller than that of the connective section; and a driving section formed at an end of the neck.
 5. The method according to claim 4, wherein the connective section of the bit includes a cavity defined therein.
 6. The method according to claim 4, wherein the driving section of the bit is a hexagonal section.
 7. The method according to claim 4, wherein the driving section of the bit is a flower-like section.
 8. A method for making a bit of a tool including the steps of: providing a blank in the form of a circular rod with a size according to that of the bit; providing at least one mold; forging the blank with the mold so that the blank includes: a connective section with a hexagonal profile, a first chamfer at an end thereof, and a second chamfer at another end thereof; and a neck extending from the connective section, wherein the width of the neck is smaller that of the connective section; squeezing a portion of the neck into a driving section with a reduced size.
 9. The method according to claim 8, wherein the connective section of the bit includes a cavity defined therein.
 10. The method according to claim 8, wherein the driving section of the bit is made with a flat configuration. 